Two students use the same stock solution of ZnSO₄ and solution of CuSO₄. The emf of one cell is 0.03 V higher than other. The conc. of CuSO₄ in the cell with higher emf value is 0.5 M. Find out the conc. of CuSO₄ in the other cell (2.203 RT/F = 0.06)

The standard potential of the following cell is 0.23V at 15^oC and 0.21 V at 35^oC.
Pt | H₂ (g) | HCl (aq) | AgCl (s) | Ag (s)
(i) Write the cell reaction.
(ii) Calculate $$\Delta H^o$$ and $$\Delta S^o$$m for the cell reaction by assuming that these quantities remain unchanged in the range 15^oC to 35^oC.
(iii) Calculate the solubility of AgCl in water at 25^oC
Given : The standard reduction potential of the Ag⁺ (aq) / Ag (s) couple is 0.80 V at 25^oC

Copper sulphate solution (250 mL) was electrolysed using platinum anode and a copper cathode. A constant current of 2mA was passed for 16 minutes. It was found that after electrolysis the absorbance of the solution was reduced to 50% of its original value. Calculate the concentration of copper sulphate in the solution to begin with.

The following electrochemical cell has been set up.
Pt(1) | Fe³⁺, Fe²⁺ (a = 1) | Ce⁴⁺, Ce³⁺ (a=1) | Pt(2)
E^o (Fe³⁺, Fe²⁺) = 0.77 V; E^o (Ce⁴⁺, Ce³⁺) = 1.61 V
If an ammeter is connected between the two platinum electrodes, predict the direction of flow of current. Will the current increase or decrease with time?